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PURPOSE: This study aimed to investigate the effects of a self-monitoring intervention to promote an increase in physical activity, as measured by step count, and reduce sedentary behavior in older people covered by the long-term care insurance system (LTCI) in Japan. METHODS: This was a randomized controlled trial conducted at a daycare center from October 2022 to January 2023. Fifty-two older adults with LTCI who were able to walk with or without aids were assigned to an intervention (n = 26) group and control (n = 26) group. During the 5-week follow-up period, the intervention group received education on physical activity and self-monitoring such as goal setting, self-management and feedback. The primary outcome was step count, and the secondary outcome was sedentary behavior. RESULTS: Participants who completed the study to the end of the 5-week follow-up and drop-out participants for whom outcome data were available were included in the final analysis of 57 participants, n = 24 (79.8 ± 8.8 years, male 25.5%) in the intervention group and n = 23 (82.5 ± 8.5 years, male 39.1%) in the control group. Comparisons between the two groups at baseline showed no significant differences. In the results of a two-way mixed analysis of variance (ANOVA) including 2 (group: control, intervention) × 2 (term: baseline, 5-week follow-up) factors, an interaction was observed in the number of steps, sedentary behavior, and light physical activity (p < 0.05). CONCLUSION: Self-monitoring of physical activity using an accelerometer may be effective in increasing the number of steps and light physical activity and in reducing sedentary behavior in older people with LTCI. CLINICAL TRIAL REGISTRATION: UMIN000052044, registered on 2023/08/29.
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Ejercicio Físico , Seguro de Cuidados a Largo Plazo , Anciano , Humanos , Masculino , Acelerometría , Japón , Caminata , Femenino , Anciano de 80 o más AñosRESUMEN
(1) Background: This study examined the differences in changes in physical function with and without falls after daycare use among frail older adults with long-term care insurance (LTCI). (2) Methods: In this retrospective cohort study, 82 of 96 consecutive daycare center users met the inclusion criteria. The participants were divided into two groups based on the presence or absence of falls 6-12 months after use. Participant characteristics in the fall and non-fall groups and physical function at baseline and six months in each group were compared. Using analysis of covariance, we analyzed physical function and its changes between the two groups, and cut-off values were calculated using receiver operating characteristic curves. (3) Results: Gait speed, timed up-and-go test, and 30 s chair stand test (CS30) improved significantly over six months in the no-fall group (n = 70) and all participants (n = 82) (p < 0.01). Gait speed in the fall group (n = 12) improved significantly over six months (p = 0.04). The fall group had significantly lower adjusted ΔCS30 scores than the no-fall group (p = 0.03), with a cutoff value of 2 (p = 0.024). (4) Conclusions: In older adults with LTCI, physical function with and without falls after daycare use differed by ΔCS30, with a cutoff value of 2.
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[Purpose] This study aimed to clarify whether collaborative learning could be promoted via information and communication technology education using tablets at college of physical therapy. [Participants and Methods] An online survey was conducted to evaluate collaborative learning among 81 first-year students at the Department of Physical Therapy actively using tablets in classes (six specific categories). [Results] The Friedman test had significant results, and a significant primary effect was observed between each questionnaire item. Following this, the Bonferroni test was performed for multiple comparisons, with significant differences were observed among certain items. [Conclusion] We reported employing tablets in the classroom positively impacted collaborative learning. Here, among the evaluations of collaborative learning, the items with the best results corresponded mainly to communication activation between students.
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Patient-derived induced pluripotent stem cells (iPSCs) provide a powerful tool for identifying cellular and molecular mechanisms of disease. Macular telangiectasia type 2 (MacTel) is a rare, late-onset degenerative retinal disease with an extremely heterogeneous genetic architecture, lending itself to the use of iPSCs. Whole-exome sequencing screens and pedigree analyses have identified rare causative mutations that account for less than 5% of cases. Metabolomic surveys of patient populations and GWAS have linked MacTel to decreased circulating levels of serine and elevated levels of neurotoxic 1-deoxysphingolipids (1-dSLs). However, retina-specific, disease-contributing factors have yet to be identified. Here, we used iPSC-differentiated retinal pigmented epithelial (iRPE) cells derived from donors with or without MacTel to screen for novel cell-intrinsic pathological mechanisms. We show that MacTel iRPE cells mimicked the low serine levels observed in serum from patients with MacTel. Through RNA-Seq and gene set enrichment pathway analysis, we determined that MacTel iRPE cells are enriched in cellular stress pathways and dysregulation of central carbon metabolism. Using respirometry and mitochondrial stress testing, we functionally validated that MacTel iRPE cells had a reduction in mitochondrial function that was independent of defects in serine biosynthesis and 1-dSL accumulation. Thus, we identified phenotypes that may constitute alternative disease mechanisms beyond the known serine/sphingolipid pathway.
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Retinopatía Diabética , Células Madre Pluripotentes Inducidas , Telangiectasia Retiniana , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Telangiectasia Retiniana/metabolismo , Telangiectasia Retiniana/patología , Retinopatía Diabética/metabolismo , Mitocondrias/metabolismo , Células Epiteliales/metabolismo , Serina/metabolismoRESUMEN
BACKGROUND: Scleral cross-linking is a potential method to inhibit axial elongation of the eye, preventing the progression of pathological myopia. Formaldehyde releasers, which are common preservatives found in cosmetics and ophthalmic solutions, have been shown to be not only effective in cross-linking corneal collagen in vitro and in vivo, but also have minimal toxicity effects on the eye. The present study aims to evaluate the efficacy of scleral cross-linking using sodium hydroxymethylglycinate (SMG) to inhibit eye growth using an in vivo rabbit model. METHODS: A cross-linking solution containing 40 mM SMG was delivered to the sub-Tenon's space behind the equator. The application regimen included a two-quadrant injection performed five times over 2 weeks on New Zealand White rabbits (n=5, group 1), and one-time injection followed for up to 5 days on Dutch-Belted rabbits (n=6, group 2). Group 1 was monitored serially for axial length changes using B-scan ultrasound for 5-6 weeks. Group 2 was injected with a higher viscosity solution formulation. Both groups were evaluated for thermal denaturation temperature changes of the sclera postmortem. RESULTS: Axial growth was limited by 10%-20% following SMG treatment as compared with the untreated eye. Thermal denaturation analysis showed increased heat resistance of the treated eyes in the areas of injection. Overall, the SMG treatment inhibited eye growth with few side effects from the injections. CONCLUSIONS: Cross-linking solutions delivered via sub-Tenon injection provide a potential method for limiting axial length growth in progressive myopia and could be used as a potential treatment for myopia.
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Miopía Degenerativa , Esclerótica , Conejos , Animales , Reactivos de Enlaces Cruzados/farmacología , Modelos Animales de Enfermedad , InyeccionesRESUMEN
Pathogenic variation in the ABCA4 gene is the underlying cause of Stargardt disease, the most common inherited retinal degeneration. We established an induced pluripotent stem cell line for retinal organoid research from a patient with mild disease features who is compound heterozygous for the frequent c.5882G>A (p.Gly1961Glu) missense variant and a c.4947delC (p.Glu1650Argfs*12) frameshift variant. Peripheral blood mononuclear cells were reprogrammed using a non-integrating Sendai virus approach. G-banded karyotyping was normal (46, XY) and mycoplasma testing was negative. Immunohistochemistry and RT-qPCR were performed to verify the expression of pluripotency and stemness markers (LIN28, NANOG, OCT4 and SOX2) and trilineage differentiation.
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Células Madre Pluripotentes Inducidas , Humanos , Enfermedad de Stargardt , Leucocitos Mononucleares , Transportadoras de Casetes de Unión a ATPRESUMEN
BACKGROUND: Inherited retinal dystrophies describe a heterogeneous group of retinal diseases that lead to the irreversible degeneration of rod and cone photoreceptors and eventual blindness. Recessive loss-of-function mutations in Tubulin Tyrosine Ligase Like 5 (TTLL5) represent a recently described cause of inherited cone-rod and cone dystrophy. This study describes the unusual phenotypes of three patients with autosomal recessive mutations in TTLL5. Examination of these patients included funduscopic evaluation, spectral-domain optical coherence tomography, short-wavelength autofluorescence, and full-field electroretinography (ffERG). Genetic diagnoses were confirmed using whole exome capture. Protein modeling of the identified variants was performed to explore potential genotype-phenotype correlations. RESULTS: Genetic testing revealed five novel variants in TTLL5 in three unrelated patients with retinal dystrophy. Clinical imaging demonstrated features of sectoral cone-rod dystrophy and cone dystrophy, with phenotypic variability seen across all three patients. One patient also developed high-frequency hearing loss during a similar time period as the onset of retinal disease, potentially suggestive of a syndromic disorder. Retinal structure findings were corroborated with functional measures including ffERG findings that supported these diagnoses. Modeling of the five variants suggest that they cause different effects on protein function, providing a potential reason for genotype-phenotype correlation in these patients. CONCLUSIONS: The authors report retinal phenotypic findings in three unrelated patients with novel mutations causing autosomal recessive TTLL5-mediated retinal dystrophy. These findings broaden the understanding of the phenotypes associated with TTLL5-mediated retinal disease and suggest that mutations in TTLL5 should be considered as a potential cause of sectoral retinal dystrophy in addition to cone-rod and cone dystrophies.
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Distrofias Retinianas , Proteínas Portadoras/genética , Electrorretinografía , Estudios de Asociación Genética , Humanos , Mutación/genética , Fenotipo , Distrofias Retinianas/genéticaRESUMEN
PURPOSE: To describe the longitudinal progression and phenotypic association of bilateral foveomacular vitelliform lesions in the setting of ABCA4 disease. DESIGN: Case report and cross-sectional cohort study. PARTICIPANTS: Nineteen patients with confirmed ABCA4 disease exhibiting an optical gap phenotype. METHODS: Multimodal retinal imaging across multiple visits included autofluorescence imaging, spectral-domain OCT (SD-OCT), and OCT angiography. Electro-oculogram (EOG) and full-field electroretinogram testing results were analyzed. Exome sequencing was performed for diagnostic confirmation and the verification of other variations. MAIN OUTCOME MEASURES: Light-peak-to-dark-trough ratio (Arden ratio) on EOG; thickness and en face maps of various retinal layers on SD-OCT; area measurements on 488- and 787-nm autofluorescence images; and the presence of variation in vitelliform-associated genes identified using exome sequencing. RESULTS: A 25-year-old White man presented with bilateral central vision loss due to foveal lesions consisting of vitelliform fluid. The result of EOG testing was inconsistent with bestrophinopathy (Arden ratio = 1.62), and no generalized rod or cone dysfunction was detected on full-field electroretinogram. Exome sequencing identified the pathogenic variants c.5882G>A (p.(Gly1961Glu)) and c.4139C>T (p.(Pro1380Leu)) in ABCA4 and no other vitelliform-associated genes. Significant thinning and abnormal reflectivity of photoreceptor-attributable layers as well as near-infrared autofluorescence abnormalities were found in lesion-adjacent areas. Complete resorption of the vitelliform fluid occurred after 30 months, after which the optical gap lesions exhibited an enlarged and "cavitated" appearance. Phenotypic screening for additional cases from a large ABCA4 disease database (n = 602) identified 18 additional patients at various stages of optical gap lesion formation, most of whom harbored the c.5882G>A (p.(Gly1961Glu)) variant (P < 0.001), although none had apparent vitelliform fluid. At least 5 of the 18 (31.6%) patients exhibited optical gap lesions with the distinct "cavitated" appearance, whereas the lesions remained unperturbed in the other patients over the course of examination. CONCLUSIONS: Foveomacular vitelliform deposition is a mechanistically congruent but rare manifestation of ABCA4 disease. Specifically, this disease phenotype may be clinically associated with the c.5882G>A (p.(Gly1961Glu)) allele and optical gap lesions.
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Enfermedades de la Retina , Tomografía de Coherencia Óptica , Transportadoras de Casetes de Unión a ATP/genética , Estudios Transversales , Electrorretinografía , Fóvea Central/patología , Humanos , Enfermedades de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Trastornos de la VisiónRESUMEN
Over 1,500 variants in the ABCA4 locus cause phenotypes ranging from severe, early-onset retinal degeneration to very late-onset maculopathies. The resulting ABCA4/Stargardt disease is the most prevalent Mendelian eye disorder, although its underlying clinical heterogeneity, including penetrance of many alleles, are not well-understood. We hypothesized that a share of this complexity is explained by trans-modifiers, i.e., variants in unlinked loci, which are currently unknown. We sought to identify these by performing exome sequencing in a large cohort for a rare disease of 622 cases and compared variation in seven genes known to clinically phenocopy ABCA4 disease to cohorts of ethnically matched controls. We identified a significant enrichment of variants in 2 out of the 7 genes. Moderately rare, likely functional, variants, at the minor allele frequency (MAF) <0.005 and CADD>25, were enriched in ROM1, where 1.3% of 622 patients harbored a ROM1 variant compared to 0.3% of 10,865 controls (p = 2.41E04; OR 3.81 95% CI [1.77; 8.22]). More importantly, analysis of common variants (MAF>0.1) identified a frequent haplotype in PRPH2, tagged by the p.Asp338 variant with MAF = 0.21 in the matched general population that was significantly increased in the patient cohort, MAF 0.25, p = 0.0014. Significant differences were also observed between ABCA4 disease subgroups. In the late-onset subgroup, defined by the hypomorphic p.Asn1868Ile variant and including c.4253+43G>A, the allele frequency for the PRPH2 p.Asp338 variant was 0.15 vs 0.27 in the remaining cohort, p = 0.00057. Known functional data allowed suggesting a mechanism by which the PRPH2 haplotype influences the ABCA4 disease penetrance. These associations were replicated in an independent cohort of 408 patients. The association was highly statistically significant in the combined cohorts of 1,030 cases, p = 4.00E-05 for all patients and p = 0.00014 for the hypomorph subgroup, suggesting a substantial trans-modifying role in ABCA4 disease for both rare and common variants in two unlinked loci.
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Transportadoras de Casetes de Unión a ATP , Degeneración Macular , Transportadoras de Casetes de Unión a ATP/genética , Proteínas del Ojo/genética , Frecuencia de los Genes , Humanos , Degeneración Macular/genética , Mutación , Linaje , Fenotipo , Enfermedad de Stargardt/genética , Tetraspaninas/genéticaRESUMEN
BackgroundMore than 1500 variants in the ATP-binding cassette, sub-family A, member 4 (ABCA4), locus underlie a heterogeneous spectrum of retinal disorders ranging from aggressive childhood-onset chorioretinopathy to milder late-onset macular disease. Genotype-phenotype correlation studies have been limited in clinical applicability as patient cohorts are typically small and seldom capture the full natural history of individual genotypes. To overcome these limitations, we constructed a genotype-phenotype correlation matrix that provides quantifiable probabilities of long-term disease outcomes associated with specific ABCA4 genotypes from a large, age-restricted patient cohort.MethodsThe study included 112 unrelated patients at least 50 years of age in whom 2 pathogenic variants were identified after sequencing of the ABCA4 locus. Clinical characterization was performed using the results of best corrected visual acuity, retinal imaging, and full-field electroretinogram testing.ResultsFour distinct prognostic groups were defined according to the spatial severity of disease features across the fundus. Recurring genotypes were observed in milder prognoses, including a newly defined class of rare hypomorphic alleles. PVS1 (predicted null) variants were enriched in the most severe prognoses; however, missense variants were present in a larger-than-expected fraction of these patients. Analysis of allele combinations and their respective prognostic severity showed that certain variants, such as p.(Gly1961Glu), and both rare and frequent hypomorphic alleles, were "clinically dominant" with respect to patient phenotypes irrespective of the allele in trans.ConclusionThese results provide much-needed structure to the complex genetic and clinical landscape of ABCA4 disease and add a tool to the clinical repertoire to quantitatively assess individual genotype-specific prognoses in patients.FUNDINGNational Eye Institute, NIH, grants R01 EY028203, R01 EY028954, R01 EY029315, P30 19007 (Core Grant for Vision Research); the Foundation Fighting Blindness USA, grant no. PPA-1218-0751-COLU; and Research to Prevent Blindness.
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Transportadoras de Casetes de Unión a ATP/genética , Coriorretinitis , Degeneración Macular , Edad de Inicio , Coriorretinitis/diagnóstico , Coriorretinitis/epidemiología , Coriorretinitis/genética , Coriorretinitis/fisiopatología , Electrorretinografía/métodos , Femenino , Fondo de Ojo , Frecuencia de los Genes , Estudios de Asociación Genética , Variación Genética , Humanos , Degeneración Macular/diagnóstico por imagen , Degeneración Macular/genética , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Secuencia de Proteína/métodos , Tomografía de Coherencia Óptica/métodos , Estados Unidos/epidemiología , Agudeza VisualRESUMEN
Assistive motion for sit-to-stand causes lower back pain (LBP) among caregivers. Considering previous studies that showed that foot position adjustment could reduce lumbar load during assistive motion for sit-to-stand, quantitative monitoring of and instructions on foot position could contribute toward reducing LBP among caregivers. The present study proposes and evaluates a new method for the quantitative measurement of foot position during assistive motion for sit-to-stand using a few wearable sensors that are not limited to the measurement area. The proposed method measures quantitative foot position (anteroposterior and mediolateral distance between both feet) through a machine learning technique using features obtained from only a single inertial sensor on the trunk and shoe-type force sensors. During the experiment, the accuracy of the proposed method was investigated by comparing the obtained values with those from an optical motion capture system. The results showed that the proposed method produced only minor errors (less than 6.5% of body height) when measuring foot position during assistive motion for sit-to-stand. Furthermore, Bland-Altman plots suggested no fixed errors between the proposed method and the optical motion capture system. These results suggest that the proposed method could be utilized for measuring foot position during assistive motion for sit-to-stand.
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Movimiento , Zapatos , Fenómenos Biomecánicos , Pie , Humanos , TorsoRESUMEN
Over 1200 variants in the ABCA4 gene cause a wide variety of retinal disease phenotypes, the best known of which is autosomal recessive Stargardt disease (STGD1). Disease-causing variation encompasses all mutation categories, from large copy number variants to very mild, hypomorphic missense variants. The most prevalent disease-causing ABCA4 variant, present in ~ 20% of cases of European descent, c.5882G > A p.(Gly1961Glu), has been a subject of controversy since its minor allele frequency (MAF) is as high as ~ 0.1 in certain populations, questioning its pathogenicity, especially in homozygous individuals. We sequenced the entire ~140Kb ABCA4 genomic locus in an extensive cohort of 644 bi-allelic, i.e. genetically confirmed, patients with ABCA4 disease and analyzed all variants in 140 compound heterozygous and 10 homozygous cases for the p.(Gly1961Glu) variant. A total of 23 patients in this cohort additionally harbored the deep intronic c.769-784C > T variant on the p.(Gly1961Glu) allele, which appears on a specific haplotype in ~ 15% of p.(Gly1961Glu) alleles. This haplotype was present in 5/7 of homozygous cases, where the p.(Gly1961Glu) was the only known pathogenic variant. Three cases had an exonic variant on the same allele with the p.(Gly1961Glu). Patients with the c.[769-784C > T;5882G > A] complex allele exhibit a more severe clinical phenotype, as seen in compound heterozygotes with some more frequent ABCA4 mutations, e.g. p.(Pro1380Leu). Our findings indicate that the c.769-784C > T variant is major cis-acting modifier of the p.(Gly1961Glu) allele. The absence of such additional allelic variation on most p.(Gly1961Glu) alleles largely explains the observed paucity of affected homozygotes in the population.
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Transportadoras de Casetes de Unión a ATP , Transportadoras de Casetes de Unión a ATP/genética , Alelos , Frecuencia de los Genes , Humanos , Mutación , Penetrancia , Fenotipo , Enfermedad de Stargardt/genéticaRESUMEN
IMPORTANCE: Probing differences in disease prevalence between sexes is challenging, especially in mendelian diseases. Independent replication of any association study is warranted. OBJECTIVE: To evaluate whether the recently reported association between sex and mild ABCA4 alleles among patients with autosomal recessive Stargardt disease (STGD1) is reproducible. DESIGN, SETTING, AND PARTICIPANTS: Sequencing and clinical data from 644 unrelated patients with genetically confirmed STGD1 were analyzed in a cross-sectional study at the Department of Ophthalmology, Columbia University, New York, New York. Data were collected from June 1999 to October 2020. MAIN OUTCOMES AND MEASURES: Sex, best-corrected visual acuity, and age at onset among patients with STGD1 with and without mild ABCA4 alleles. RESULTS: A total of 644 patients with STGD1 with at least 2 pathogenic variants were included in the study. The mean (SD) age was 38.6 (17.2) years, and 352 participants (54.7%) were female. The proportion of women was slightly higher in the entire cohort and in most allele categories, although none of the differences were statistically significant. The proportion of women carrying the c.5603A>T p.(Asn1868Ile) allele was 7% (95% CI, -9 to 23) higher than in the subgroup not carrying any mild alleles (P = .32). The proportion of women carrying the c.5882G>A p.(Gly1961Glu) allele was 2% (95% CI, -12 to 15) higher than in the subgroup not carrying any mild alleles (P = .77). The difference between the total mild allele subcohort and the no mild allele subcohort was 3% (95% CI, -8 to 14; P = .48). Compared with patients in the no mild allele category, patients with mild alleles exhibited significantly delayed disease onset (mean [SD] age, 23.1 [11.6] for those with the c.5882G>A allele and 31.7 [13.5] years for those with the c.5603A>T allele vs 18.6 [11.8] years for those with no mild alleles; P < .001) and preserved visual acuity (5882G>A subgroup: mean [SD] logMAR, 0.65 [0.66]; 95% CI, 0.63-0.68; c.5603A>T subgroup: 0.64 [0.39]; 95% CI, 0.58-0.70; those with no mild alleles: 1.00 [0.57]; 95% CI, 0.96-1.03; P < .001). CONCLUSIONS AND RELEVANCE: This independent analysis of a larger cohort of individuals with Stargardt disease did not support the association between sex and certain mild ABCA4 alleles. While sex is undoubtedly an important variable in medicine, its putative association with clinical outcomes should be rigorously scrutinized.
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Transportadoras de Casetes de Unión a ATP , Transportadoras de Casetes de Unión a ATP/genética , Adulto , Alelos , Estudios Transversales , Femenino , Humanos , Masculino , Mutación , Enfermedad de Stargardt/genética , Agudeza Visual , Adulto JovenRESUMEN
Macular telangiectasia type 2 (MacTel) is a progressive, late-onset retinal degenerative disease linked to decreased serum levels of serine that elevate circulating levels of a toxic ceramide species, deoxysphingolipids (deoxySLs); however, causal genetic variants that reduce serine levels in patients have not been identified. Here we identify rare, functional variants in the gene encoding the rate-limiting serine biosynthetic enzyme, phosphoglycerate dehydrogenase (PHGDH), as the single locus accounting for a significant fraction of MacTel. Under a dominant collapsing analysis model of a genome-wide enrichment analysis of rare variants predicted to impact protein function in 793 MacTel cases and 17,610 matched controls, the PHGDH gene achieves genome-wide significance (P = 1.2 × 10-13) with variants explaining ~3.2% of affected individuals. We further show that the resulting functional defects in PHGDH cause decreased serine biosynthesis and accumulation of deoxySLs in retinal pigmented epithelial cells. PHGDH is a significant locus for MacTel that explains the typical disease phenotype and suggests a number of potential treatment options.
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Haploinsuficiencia , Fosfoglicerato-Deshidrogenasa/genética , Telangiectasia Retiniana/genética , Serina/biosíntesis , Estudios de Cohortes , Humanos , Fenotipo , Epitelio Pigmentado de la Retina/metabolismoRESUMEN
[Purpose] In caregivers, low load posture is necessary to prevent lower back pain during patient handling activities such as sit-to-stand support. This study focused on the foot-position of caregivers as an adjustable and useful parameter. A wide stance decreases the stress on the lumbar vertebra. However, this foot-position increases loading of the spinae erector muscles. The aim of this study was to investigate the relationship of anterior-posterior and lateral-medial distances between feet and activity of the spinae erector muscles to determine the optimal foot-position for reducing stress on the lumbar vertebra without increasing spinae erector muscle load. [Participants and Methods] Five young male participants were asked to provide sit-to-stand support 10 times using nine normalized foot-positions with different anterior-posterior and lateral-medial distances. Surface electromyograms of the erector spinae and lower limb muscles were measured during sit-to-stand support. [Results] The results showed that the optimal foot-position (anterior-posterior 55%, lateral-medial 20% of body height) increased muscle activity within the lower limb muscles compared with the lower back muscles and did not increase loads on the erector spinae muscle. [Conclusion] Optimizing foot-position can reduce stress on the lumbar vertebra without increasing load on the spinae erector muscles.
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Purpose: A topical corneal cross-linking solution that can be used as an adjunct or replacement to standard photochemical cross-linking (UV-riboflavin) methods remain an attractive possibility. Optimal concentration and delivery method for such topical corneal stabilization in the living rabbit eye were developed. Methods: A series of experiments were carried out using Dutch-belted rabbits (3 months old, weighing 1.0-1.5 kg) and topical cross-linking solutions (sodium hydroxymethylglycinate) (10-250 mM) delivered via corneal reservoir. The application regimen included a one-time 30-minute application (10-40 mM sodium hydroxymethylglycinate) as well as a once per week 5-minute application (250 mM sodium hydroxymethylglycinate) for 7 weeks. Animals were evaluated serially for changes in IOP, pachymetry, epithelial integrity, and endothelial cell counts. Keratocyte changes were identified using intravital laser scanning confocal microscopy. Post mortem efficacy was evaluated by mechanical inflation testing. Results: Overall, there were very few differences observed in right eye treated versus left eye controls with respect to intraocular pressure, pachymetry, and endothelial cell counts, although 30-minute cross-linking techniques did cause transient increases in thickness resolving within 7 days. Epithelial damage was noted in all of the 30-minute applications and fully resolved within 72 hours. Keratocyte changes were significant, showing a wound healing pattern similar to that after riboflavin UVA photochemical cross-linking in rabbits and humans. Surprisingly, post mortem inflation testing showed that the lower concentration of 20 mM delivered over 30 minutes showed the most profound stiffening/strengthening effect. Conclusions: Topical cross-linking conditions that are safe and can increase corneal stiffness/strength in the living rabbit eye have been identified. Translational Relevance: A topical corneal cross-linking solution delivered via corneal reservoir is shown to be both safe and effective at increasing tissue strength in living rabbit eyes and could now be tested in patients suffering from keratoconus and other conditions marked by corneal tissue weakness.
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Sustancia Propia , Fármacos Fotosensibilizantes , Animales , Colágeno , Reactivos de Enlaces Cruzados , Humanos , Conejos , Rayos UltravioletaRESUMEN
[Purpose] A goniometer is frequently used for static measurement of hindfoot alignment. However, although goniometer measurements require experience, their reliability and validity remain controversial. We developed a hindfoot alignment measurement method by laser as an alternative measure. The purpose of this study was to examine the reliability of laser-assisted hindfoot alignment evaluation. [Participants and Methods] Two non-expert examiners (without medical knowledge), briefly trained in the use of laser-assisted hindfoot alignment evaluation, evaluated hindfoot alignment in 12 healthy participants. [Results] The ICC of the intra-rater reliability was 0.74 for both examiners and the ICC for inter-rater reliability was 0.43. [Conclusion] The good intra-rater and moderate inter-rater reliability of laser-assisted hindfoot alignment evaluation, when used by non-professionals, suggest the laser-assisted hindfoot alignment evaluation may be appropriate for use in clinical practice settings.
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BACKGROUND: Corneal infections with antibiotic-resistant microorganisms are an increasingly difficult management challenge and chemically or photochemically cross-linking the cornea for therapy presents a unique approach to managing such infections since both direct microbial pathogens killing and matrix stabilization can occur simultaneously. The present study was undertaken in order to compare the anti-microbial efficacy, in vitro, of 5 candidate cross-linking solutions against 5 different microbial pathogens with relevance to infectious keratitis. METHODS: In vitro bactericidal efficacy studies were carried out using 5 different FARs [diazolidinyl urea (DAU), 1,3-bis(hydroxymethyl)-5,5-dimethylimidazolidine-2,4-dione (DMDM), sodium hydroxymethylglycinate (SMG), 2-(hydroxymethyl)-2-nitro-1,3-propanediol (NT = nitrotriol), 2-nitro-1-propanol (NP)] against 5 different microbial pathogens including two antibiotic-resistant species [methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), Pseudomonas aeruginosa (PA), and Candida albicans (CA)]. Standard in vitro antimicrobial testing methods were used. RESULTS: The results for MSSA were similar to those for MRSA. DAU, DMDM, and SMG all showed effectiveness with greater effects generally observed with longer incubation times and higher concentrations. Against MRSA, 40 mM SMG at 120 min showed a > 95% kill rate, p < 0.02. Against VRE, 40 mM DAU for 120 min showed a > 94% kill rate, p < 0.001. All FARs showed bactericidal effect against Pseudomonas aeruginosa, making PA the most susceptible of the strains tested. Candida showed relative resistance to these compounds, requiring high concentrations (100 mM) to achieve kill rates greater than 50%. CONCLUSION: Our results show that each FAR compound has different effects against different cultures. Our antimicrobial armamentarium could potentially be broadened by DAU, DMDM, SMG and other FARs for antibiotic-resistant keratitis. Further testing in live animal models are indicated.
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Antibacterianos/farmacología , Antifúngicos/farmacología , Bacterias/efectos de los fármacos , Candida albicans/efectos de los fármacos , Formaldehído/metabolismo , Úlcera de la Córnea/tratamiento farmacológico , Úlcera de la Córnea/microbiología , Resistencia a Medicamentos , Farmacorresistencia Bacteriana , Infecciones Bacterianas del Ojo/tratamiento farmacológico , Infecciones Bacterianas del Ojo/microbiología , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Infecciones Fúngicas del Ojo/microbiología , Pruebas de Sensibilidad Microbiana , Nitrocompuestos/farmacología , Propanoles/farmacología , Sarcosina/análogos & derivados , Sarcosina/farmacología , Trometamina/análogos & derivados , Trometamina/farmacología , Urea/análogos & derivados , Urea/farmacologíaRESUMEN
Hyperviscosity agents are commonly used in ophthalmic formulations for improving corneal drug penetration by increasing tissue contact time. One such viscosity agent is hydroxypropyl methylcellulose (HPMC). HPMC has been used in riboflavin solutions for photochemical UVA cross-linking (CXL). Sodium hydroxymethylglycinate (SMG) is a small molecule formaldehyde releaser that can function as a therapeutic tissue cross-linker for corneal and scleral applications. The present study was undertaken in order to study formulation factors using HPMC and SMG that could positively influence the cross-linking effect in these ocular tissues. Formulations containing 10 mM SMG and 100 mM sodium bicarbonate were prepared with varying HPMC concentrations from 0 to 4.4%. Their cross-linking effects on porcine and rabbit eyes were measured using differential scanning calorimetry (DSC), expressed as the change/difference in melting temperature (ΔTm) compared with the control. SMG in 4.4% HPMC solution resulted in ΔTm of 6.3 ± 1.21, while other concentration showed no differences in Tm shift on porcine cornea. In ex vivo rabbit cornea, there was a trend toward an increasing cross-linking effect with higher viscosity albeit mild differences. While a significant Tm shift was observed in porcine and rabbit sclera, there was no difference in effect of cross-linking between four HPMC concentrations. Increasing the HPMC concentration does not negatively affect the cross-linking efficacy attributed by SMG and could still be a positive cross-linking enhancer by virtue of increasing tissue contact time in a dynamic biological system. This information will be useful for planning further animal and human studies.
Asunto(s)
Reactivos de Enlaces Cruzados/química , Sarcosina/análogos & derivados , Viscosidad/efectos de los fármacos , Animales , Química Farmacéutica/métodos , Córnea/efectos de los fármacos , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/química , Conejos , Riboflavina/administración & dosificación , Riboflavina/química , Sarcosina/química , Esclerótica/efectos de los fármacos , PorcinosRESUMEN
[Purpose] Caregivers experience low back pain owing to frequent patient handling motions such as supporting the body while standing up. To prevent low back pain in caregivers, low load posture while engaging in patient handling motions is required. We determined the relationship between surface electromyography of the erector spinae muscles and subjective step length as "long" and "short" during the supporting standing-up motions of caregivers. [Participants and Methods] Ten young male participants were asked to perform supporting standing-up motion 10 times using two-step lengths comprised of subjective long and short steps. During supporting standing-up motion, we measured surface electromyograms of the erector spinae muscles and calculated the integral electromyographic values. [Results] The subjective long/short-step length normalized by body height did not differ across the participants. In addition, the subjective long-step length was longer than the subjective short-step length in all the participants. Integral electromyographic values for both the left and right erector spinae muscles in the short-step length were significantly lower than those in the long-step length when the data obtained from all the participants were used. [Conclusion] We considered that the load of the erector spinae muscle will be reduced if the short-step instead of the long-step instruction is given. In the future, instructions based on the subjective step-length variation in caregivers must be considered.